Three-dimensional preoperative planning accurately guides surgeons for intraoperative implant selection in shoulder arthroplasty

Abstract Background With the rapid growth of shoulder arthroplasty (SA) over the past decade, the focus has been on improving outcomes and minimizing complications. As a result, preoperative planning tools have become a trend among orthopedic surgeons for SA to aid in achieving optimal implant selection and ultimately continual improvement of outcomes. Success in achieving these goals is predicated on software precision and reliability. Therefore, the purpose of our study was to assess the accuracy of three dimensional (3D) preoperative planning software in guiding orthopaedic surgeons for implant selection in SA. Methods This was a retrospective study of 76 patients who underwent SA all with the same manufacturer's implants by a single fellowship-trained shoulder surgeon. All patients had preoperative CT scans and completed 3D preoperative plans. The final implant selection was decided intraoperatively solely under surgeon's discretion based on review of preoperative plan, intraoperative bone quality, and soft tissue balancing, not restricted by the preoperative plan. Software accuracy was assessed by directly comparing each component size planned to the actual implant selected in the procedure for both humeral and glenoid components. Statistical analyses was performed including paired-sample t tests and rate for perfect matching. Results Our results demonstrated glenoid implant size matched perfectly in 75% of cases and 100% within 1 size in anatomic total shoulder arthroplasty (TSA). Humeral head diameter matched perfectly in 31% of cases and 100% within 1 size. Humeral head thickness matched perfectly in 69% of cases and 100% within 1 size. For reverse shoulder arthroplasty, glenoid baseplate diameter matched perfectly in 81% of the cases and 100% within 1 size. Glenosphere diameter matched perfectly in 88% of the cases and 98% within 1 size. Humeral stem size in both groups were more variable than the remaining components. Conclusion Our study demonstrates that 3D preoperative planning was accurate to guide intraoperative implant selection for both anatomic and reverse SA including both glenoid and humeral components within 1 size. This tool may decrease the need for extensive inventory and instrumentation by improving operating room workflow and surgeon efficiency and may ultimately be translate into better postoperative outcomes. Level of evidence Level IV; Case Series